My truck didn’t come with a radio, but the wiring was there so I bought a cheap unit off Amazon and tossed it in. All good on the test run so I put the panels all back in, and then the radio wouldn’t shut off…so I figured out that the clock was somehow back-feeding the radio and causing it to stay on, clock has 12v constant as well as 12v switched, it is off when the key is off. Unplugged the clock and all is good, radio has a clock so no big deal, but I prefer all my stuff to work, so this will bug me, lol. Anyone seen this before? I’m gonna try to find a replacement clock but not sure how that will go.
Why are you tapped into the clock? Radio has its own wiring. on the HU Yellow- constant, Red- switched
I’m not tapped into anything, ran everything through the original radio plug, but the radio and the clock appear to share a power feed (main power is blue/yellow), and the switched feed as well (grey).
Im going to go ahead and guess you tested the wires with a DMM. Are you using an adapter harness between the HU and factory wiring?
I didn’t test the clock wires, no. I plan to verify with a wiring diagram but I figured I’d ask here first to see if it’s common, but it seems there’s only a few active members here. Also, no I couldn’t get a harness adaptor for at least 3 weeks, so I tested the wires in the connector, unpinned them all and used some opposite pins that I had to wire it in, this way the factory wiring is not damaged, and I can use my stereo without waiting so long for a harness. Everything works as long as the clock is disconnected, the clock works normally though and doesn’t stay on, pretty strange.
Its available on amazon Metra 70-1761 Radio Wiring Harness For Toyota 87-Up Power 4 Speaker https://a.co/d/8sHxUYJ
Well damn. I searched on Amazon (.ca) and only found one from China, woulda been 3 weeks minimum plus import fees and crap. No matter, it’s wired properly, I checked the pins and there’s only 4 other than speakers, those are power, ign power, ground, and illumination. Im wondering if it’s got something to do with the after,ark et alarm/starter kill…was in it when I bought it.
That's possible. Could always just check for continuity between the stereo and clock wires and see if and where they meet
Well I know they meet, just not sure where, or why. I didn’t even think about the alarm when I posted this, but I’m guessing I’ll need to tear into it to fully diagnose this, that will be a winter project as I’m not taking it apart again now, I’m enjoying driving it too much.
Ya, but now that you found it for me I ordered the harness for tomorrow, lol, I hate doing stuff half-assed, even if it works. Cost me $18 btw, quite a difference. I think I’ll swap it out and yank the alarm at the same time.
I feel you bro, had to swap a stereo in my chevy that i got from my dad and BRUH whoever installed should stay away from anything automotive
The issue you're facing, where the clock back-feeds power to the radio, could be due to a wiring anomaly or a fault in the clock unit. Replacing the clock might resolve the problem, ensuring it doesn't interfere with the radio's power supply. Verify the wiring connections and check if there are any crossed wires. If the problem persists, consider consulting with a car audio professional for a more in-depth diagnosis. Finding a compatible replacement clock with proper voltage regulation is key to maintaining functionality without causing unintended issues with other electrical components in your truck.
